Anatomy Embryology 1.3 :: Incomplete

Front 1

During Implantation (8th day), trophoblastic differentiation occurs creating what two types of cells?

Back 1

Cytotrophoblasts -inner

Syncytiotrophoblasts -outer

Front 2

Inner layer of mitotically active mononuclear cells with distinct boundaries

Back 2

cytotrophoblasts

Front 3

outer mass of cells without cell boundaries known as a syncytium that lack of mitotic activity and are derived from cytotrophoblasts

Back 3

syncytiotrophoblasts

Front 4

What are syncytiotrophoblasts derived from?

Back 4

cytotrophoblasts

Front 5

Formed as fluid accumulates between trophoblasts and embryoblasts

Back 5

amniotic cavity

Front 6

the inner cell mass becomes organized into two layers

Back 6

bilaminar germ disc

-epiblasts

-hypoblasts

Front 7

layer of columnar epithelium adjacent to the amniotic cavity in the bilaminar germ disc

Back 7

Epiblasts

Front 8

the cuboidal layer adjacent to the blastocyst cavity now know as the primitive yolk sac in the bilaminar germ disc

Back 8

hypoblasts

Front 9

blastocyst cavity becomes the ?

Back 9

primitive yolk sac

Front 10

By the 9th day, only a ? plug demarcates the site of implantation

Back 10

fibrin

Front 11

By what day does the implantation site covered by endometrium?

Back 11

day 12

Front 12

By day 9, vacuoles form within the ? and fuse to form lacunar networks.

Back 12

Syncytiotrophoblasts

Front 13

As the syncytial cells erode away, maternal vessels and blood flow into the lacunar network and initiate ?

Back 13

Uteroplacental circulation

Front 14

a layer of loosly associated cells form between cytotrophoblasts and the primitive yolk sac.

Back 14

Extraembryonic mesoderm

Front 15

The coalescence of large cavities that form within the extraembryonic mesoderm

Back 15

extraembryonic coelom

(chorionic cavity)

Front 16

The chorionic cavity seperates the extraembryonic mesoderm into?

Back 16

extraembryonic SOMATIC mesoderm

extraembryonic VISCERAL mesoderm

Front 17

A person has a "last menstrual period"

Back 17

occurs at the implantation site due to increased blood flow into the lacunar networks

Front 18

What is the Decidual Reaction?

Back 18

swelling of endometrial tissues edema

--> accumulation of glycogen and lipid in the endometrium

=> immediately surround the embryo and soon incites the entire endometrium

Front 19

What is the ideal implantation site?

Back 19

dorsal or ventral wall

near the Fundus (cranial end of uterus)

Front 20

What are the 3 types of ectopic pregnancies?

Back 20

Ductal (oviduct)

Internal os

Abdominal

Front 21

Placenta pervia is caused by?

Back 21

ectopic pregnancy in the Internal Os of the cervix

dangerous during 2nd trimester and at delivery

Front 22

An abdominal ectopic pregnancy usually attaches in the ?

Back 22

rectouterine cavity (douglas' pouch)

Front 23

Trophoblastic maturation => primary villi

what are they composed up of?

Back 23

cytotrophoblastic (fingers)

surrounded by syncytiotrophoblasts

Front 24

Secondary yolk sac is formed from expansion of the ? reshaping the primitive yolk sac

Back 24

chorionic cavity

Front 25

Connecting stalk expansion of the ? nearly isolates the developing embryo from the trophoblasts except near the caudal end of the embryonic disc

Back 25

Chorionic cavity

Front 26

Describe the 2nd week:

"rules of 2"

Back 26

2 germ layers
-epiblasts
-hypoblasts

2 embryonic cavities
-amnion
-yolk sac

2 trophoblastic layers
-cytotrophoblasts
-syncitiotrophoblasts

Front 27

a midline indentation of the epiblast surface extending midway into the disc from the caudal end

Back 27

primitive streak

Front 28

a slightly enlarged indentation at the cranial tip of the primitive streak

Back 28

primitive pit

Front 29

elevated region that surround the primitive pit

Back 29

primitive node / knot

Front 30

early invagination of cells through the primitive pit migrate cranially

Back 30

prechordal plate

Front 31

early invagination of cells through the primitive pit migrate cranially, displace hypoblast, thicken and fuse with the epiblast forming the ?

Back 31

oropharyngeal membrane

Front 32

Cells of the epiblast proliferate and migrate toward and down through the primitive streak in a process called ?

Back 32

invagination

Front 33

first wave of invaginating cells that displace the hypoblast cell layer

Back 33

embryonic endoderm

Front 34

invaginating cells that take residence between the developing embryonic endoderm and the overlying epiblast

Back 34

embryonic mesoderm

Front 35

epiblasts cells that remain after gastrulation

Back 35

embryonic ectoderm

Front 36

What is Gastrulation?

When does it occur?

Back 36

formation of mesoderm, endoderm, and ectoderm

day 14 - day 19

Front 37

Suspected remnants of the primitive streak or displaced primordial germ cells

common in what region?

Back 37

Teratomas


Sacrococcygeal region

Front 38

Cells invaginating in trhgouh the primitive pit/know form a solid rod of ? this is called the ?

migrates cranially until it abut the prochordal plate/oropharnygeal membrane

Back 38

mesoderm

Notochord

Front 39

The notochord serves as the basis of the ?

Back 39

axial skeleton in the midline and establishes right and left orientation

Front 40

Migrating mesoderm passes around the fused oropharyngeal membrane and a similar caudal epiblast/endoderm fusion called the ?

Back 40

cloacal membrane

Front 41

True or False

Invaginating cells which become embryonic mesoderm spread cranially, laterally, and caudally.

Back 41

True

Front 42

Abnormalities in the cranial migration and fusion beyond the prochondral plate of mesoderm cause defects in the development of the ?

Back 42

heart

Front 43

Abnormalities in the caudal migration and fusion beyond the cloacal membrane of mesoderm cause defects in the ?

Back 43

lower abdominal wall

bladder

Front 44

During the formation of the notochord the posterior wall of the secondary yolk sac forms a diverticulum called the ? which extends into the connecting stalk.

Back 44

allantois

Front 45

What is the role of the allantois?

Back 45

may play a role in the induction of ANGIOGENESIS

(blood and blood vessel development)

Front 46

True or False

Germinal disc changes shape --

initially flat and round (frisbee)

expands Cranially and laterally to resemble a pear

Back 46

True

Front 47

Primary villi are penetrated --forming secondary villi by what type of cells?

Back 47

extraembryonic somatic mesoderm

Front 48

Tertiary villi (definitive villi) give rise to formation of ?

This occurs in the extraembryonic mesoderm of secondary villi

Back 48

blood islands and primitive vessels

Front 49

? develops vessels that convey blood from the developing placental blood vessels (from villi and the chorionic plate) to the developing embryonic circulation

Back 49

connecting stalk

Front 50

Within the ? connecting vessels begin to develop the same time that tertiary villi are emerging.

Back 50

Chorionic Plate

Front 51

REMEMBER

chorionic plate
tertiary villi
connecting stalk

all give rise to blood structure

Back 51

REMEMBER

chorionic plate
tertiary villi
connecting stalk

all give rise to blood structure

Front 52

cytotrophoblasts that have penetrated through the syncytium to the decidua

--firmly attaching the chorion (placenta) to the endometrium

Back 52

Cytotrophoblastic shell

Front 53

Villi which extend from the chorionic plate to the decidua

Back 53

stem / anchoring villi

Front 54

Side branches of villi exxtending from the anchoring villi

Back 54

free villi